1. Mastering in Sciences by the College of Medical Sciences at University of the State of Rio de Janeiro (UERJ). Rio de Janeiro, RJ, Brazil. Nutritionist at the School of Health Sciences, Rio Grande University (Unigranrio). Duque de Caxias, RJ, Brazil
2. Doctorate in Clinical Medicine by the Federal University of Rio de Janeiro (UFRJ). Rheumatologist at the Department of Rheumatology, Center for Adolescent Health Studies (NESA), Pedro Ernesto University Hospital (HUPE), State University of Rio de Janeiro (UERJ). Rio de Janeiro, RJ, Brazil
3. Doctorate in Sciences from the State University of Rio de Janeiro (UERJ). Nutritionist at the Division of Nutrition in the Center for Adolescent Health Studies (NESA), Pedro Ernesto University Hospital (HUPE), State University of Rio de Janeiro (UERJ). Rio de Janeiro, RJ, Brazil

Abstract:OBJECTIVE: Determine the frequency of metabolic syndrome and its components in adolescents with systemic lupus erythematosus. METHODS: A cross-sectional study was carried out at the Rheumatology Outpatient Clinic of the Center for the Study of Adolescent Health at Pedro Ernesto University Hospital. We analyzed adolescents from 10 to 19 years old with diagnosis of systemic lupus erythematosus. Metabolic syndrome was diagnosed through the criteria of the Internation Diabetes Federation. Were analyzed Clinical, sociodemographic, laboratorial variables, and physical activity. RESULTS: The study evaluated 42 adolescents with a mean age of 16.8 ± 1.5 years, of which 37 (88%) were female and five (12%) were male. The Metabolic Syndrome was diagnosed in seven lupus patients (16.7%), all of whom were between 17 and 19 years old. Sedentarism, disease activity and unfavorable socioeconomic conditions were the variables most associated with the presence of metabolic syndrome in adolescents. Among the components that integrate it, high waist circumference, hypertension and low HDL-c were the most prevalent. CONCLUSION: This study made it possible to conclude that the adolescents with the highest prevalence of metabolic syndrome belonged to the female sex, with ages ranging from 17 to 19 years old, attending high school, with a family income of less than three minimum wages. The most frequent clinical features were obesity, use of antimalarials, sedentary and with time of disease diagnosis in the period of 1 to 3 years.

Systemic Lupus Erythematosus (SLE) is an autoimmune, multisystem inflammatory disease of unknown origin characterized by the presence of several autoantibodies1. It is reported in the literature that lupus patients are more likely to develop cardiovascular events, although their mechanism is still unknown. It is proposed that lupus itself, as an inflammatory disease, triggers chronic activation of the immune system, with increased stimulation of inflammatory cytokines, leading to the formation of premature atherosclerosis2.

Among the modifiable risk factors for atherosclerosis in adolescents with SLE, obesity, systemic arterial hypertension (SAH), insulin resistance, diabetes mellitus, dyslipidemia - high low density lipoprotein - Low Density Lipoprotein (LDL), increased triglycerides (HDL), smoking, increased homocysteine and interleukins (IL-1), (IL-6) and (IL-8)³. Non-modifiable factors include age, sex, genetics, and family history. Modifiable cardiovascular risk factors are more prevalent in lupus patients, leading to changes in the vascular endothelium integrity, with presence in the active phase or remission of the disease4.

Metabolic syndrome (MS) is a set of risk factors for cardiovascular diseases, including abdominal obesity, insulin resistance, hypertension and dyslipidemia5. MS became a frequent disorder in Brazil, affecting about 7.5% to 30% of the Brazilian population, being considered a major public health problem6.

A study carried out with lupus patients showed a high prevalence of overweight, which increases the chance of SM7 development by 50%. It reinforces the magnitude with which these individuals are susceptible to the development of metabolic disorders throughout the therapy, being of great importance the early detection of metabolic alterations that enable measures to stimulate the improvement of the quality of life and health promotion8. the lack of studies on the metabolic profile of adolescents with SLE. In view of this, the objective of this study was to determine the frequency of MS, and its components in adolescents with SLE.

METHOD

A cross-sectional study was carried out at the Rheumatology outpatient clinic of the Center for the Study of Adolescent Health at the Pedro Ernesto University Hospital. All the adolescents diagnosed with SLE9 of both sexes, aged between 10 and 19 years, who signed the free and informed consent form, participated in the study. The exclusion criteria were inability to stay in orthostatism or in the supine position to perform the nutritional evaluation.

The anthropometric measures were weight (kg), measured by a Micheletti scale with a capacity of 200kg and a graduation of 0.05kg, and stature (cm) with the aid of a stadiometer fixed to the wall of the Sanny brand with an accuracy of 0, 1 cm. Body mass index (BMI) was calculated according to weight (kg) / height (m2), with a subsequent classification of nutritional status, according to criteria established for adolescents of the World Health Organization (WHO) in 200710. Waist circumference (CC) was used in millimeter inelastic tape at the midpoint between the last fixed rib and the upper border of the right iliac crest, measured at the end of a normal expiration. For the classification of CC, the parameters of Freedman11 were used. Criteria for diagnosis of MS were performed according to the recommendations of the International Diabetes Federation (IDF) 12 as shown in table 1.

Patients were selected in groups with one, two or more of two components of MS. The diagnostic criteria referred to by the IDF (2007)12 were abdominal obesity - which includes waist circumference increased according to a percentile> 90 for age and sex, triglycerides> 150mg / dl, HDL <40mg / dl, systolic blood pressure 130 and diastolic ≥ 80mmHg, or use of hypotensive medication, fasting glycemia ≥ 100mg / dl or use of hypoglycemic medication. For the evaluation of fasting glycemia, the enzymatic hexokinase method was used, for the dosage of triglycerides, total cholesterol and HDL was used the enzymatic colorimetric method. Laboratory tests were performed in the hospital's own laboratory after an indication of a 12-hour fast.

Data referring to schooling and family income were extracted from patients' charts. The arterial pressure (BP) was measured in the right arm with appropriate cuff, determined by the arm circumference (CB), covering approximately 80% of the distance between the olecranon and the acromion, using the oscillometric method, using the Omron 705 -IT®. Three measures were performed with a three-minute interval, after the teenager rested for five minutes. Adolescents with systolic and / or diastolic BP below the 90th percentile for height, gender and age were considered normotensive; with borderline BP, if systolic and / or diastolic BP were between the 90th and 95th percentiles; such as hypertension, systolic and / or diastolic BP above the 9513 percentile.

The Physical Activity Questionnaire 36 Questionnaire for Older Children (PAQ-C) was applied in the investigation of the level of physical activity. Those who scored> 300 minutes / week were classified as active and those <300 minutes / week, inactive. Subjects with a level above 2,100 minutes / week of physical activity were excluded from this variable14.

The SLEDAI index (Systemic Lupus Erythematosus Disease Activity Index) was used to determine disease activity in adolescents with SLE15 and a ≥ 3 cutoff value was used to classify disease activity. The use or not of corticosteroids and antimalarial was analyzed, adopting as a cutoff the continuous administration of at least one month of use16.

For the analysis of data, they were first stored in a spreadsheet of the Excel version 7 software. Later, they were analyzed through the software STATA version 10. The continuous variables were described by mean and standard deviation and the categorical ones, by proportion. The variables were tested using the Kolgomorov-Smirnov test to verify if they had a normal distribution. Those with normal distribution were compared using Student's t-test and those with non-parametric distribution using the Mann-Whitney test. For the categorical variables, the chi-square test was used. For all analyzes, a value of (P <0.05) was adopted for significance.

RESULTS

42 adolescents were analyzed, being 37 girls (88%) and 5 boys (12%). The mean age was 16.8 ± 1.5 years. As to the classification of nutritional status, a greater number of eutrophic individuals (57.1%) were followed, obese (26.2%), overweight (12%) and low weight (4.7%). It was observed that 24 adolescents used steroids (57.2%) and 37 antimalarials (88.1%). In relation to the disease activity, the SLEDAI index was altered in 23 patients (54.7%). The other results are shown in table 2.

In the individual analysis of the MS components, 15 adolescents (35.7%) presented two risk factors, 13 (30.9%) presented a risk factor and no patient presented the four components used in the IDF criteria. MS was diagnosed in seven patients (16.7%). Of these, five (71%) were female and two (29%) were male. Of the seven adolescents diagnosed with MS, all were between the ages of 17 and 19, and six of these (85%) had family income ≤ 3 minimum wages. In the same context, it was observed that in the SM group, five (71%) presented SLEDAI ≥ 3. As shown in table 3, the mean BMI was significantly higher in the individuals with SM presence (p = 0.006) when compared with the mean of those without MS (28.4kg / m2 vs. 23.6kg / m2). For CC, a statistically significant mean (p = 0.0006) was found in those with MS. As for fasting glycemia, it was higher in adolescents with MS. A relevant aspect in this study was the percentage of sedentary adolescents in the study (62.5%), and of these, 24% had MS. Table 4 shows the frequency of the SM components, where elevated blood pressure, hypertension and low HDL were the most prevalent.

DISCUSSION

In this study, the frequency of MS was 16.7%. Ford et al. found a predominance of 4.5% of MS using diagnostic IDF in a population of healthy American adolescents17. Another study carried out with 79 obese adolescents showed a prevalence of 45.5% of SM18. Regarding the diagnostic criteria for MS stratified in relation to nutritional status, in the present study it was confirmed that MS was more prevalent in obese patients (27.3%).

The percentage of overweight measured in the study was 38.2%. The research developed by Mina et al. with children and adolescents with SLE, showed a prevalence of 25% of obesity in a sample of 202 patients, where this metabolic disorder correlated with a negative impact on quality of life, including reduction of physical capacity, social and emotional dysfunction19. The study performed by Sinicato et al. Revealed a frequency of 31% of obese Lupus adolescent, associated with high levels of inflammatory cytokines, with statistical significance for TNF-alpha20.

The treatment of SLE is individualized with respect to administered drugs and their dosages, depending on the degree of organ or tissue impairment21. Glucocorticoids are the drugs most used in the treatment of SLE, and their daily doses will differ according to individualized protocol22. According to a study by Mok et al., Which evaluated 29 lupus patients for seismic, it was observed that those who used high doses of corticosteroids had a correlation with changes in BMI, increase of fat percentage and reduction of lean mass23. In this study, more than half of lupus adolescents used steroids and most used antimalarials. A study by Reis et al.24 found a frequency of 93.7% of prednisone use and 69.6% of antimalarials.

The frequency of adolescents considered active according to IPAQ-C was 37.5% (n = 15). Considering the total sample, about 62.5% (n = 25) of the adolescents analyzed were considered sedentary, and of these, 24% (6) had MS, corroborating the importance of practicing physical activity in the prevention of risk factors for MS . The literature reinforces the importance of improving the body composition of lupus patients with physical activity, as well as resistance to exercise, better cardiorespiratory capacity and quality of life, without stimulating disease activity25.

The SLEDAI index, used to classify disease activity, was altered by more than 50% in the sample, indicating disease activity. In the research performed with lupus women in the University Hospital of the Federal University of Mato Grosso do Sul (HU-UFMS), there was a 22.1% change26.

After analysis of the components alone, CHD was altered in 31% of adolescents with lupus. It is assumed that CC elevation becomes an aggravating factor of MS in children and adolescents and could be used to identify risk of CVD in clinical practice27.

Mean fasting blood glucose levels remained higher in adolescents with MS when compared to those without MS. A study by Sánchez-Pérez et al. verified the presence of IR through HOMA-IR and C-peptide analyzes in individuals with SLE, when compared to the control group28. Although our data have not verified IR in lupus adolescents, it is known that it is important to periodically monitor this parameter as a form of prevention for chronic non-communicable diseases, such as Diabetes mellitus29.

Elevated levels of LDL cholesterol and low HDL are closely related to the atherogenesis process30. However, in this study no significant value was found that related HDL to MS. However, the values of LDL and total cholesterol (CT), although not part of the diagnosis recommended by the IDF, remained high in those with SM. The presence of dyslipidemia aggravates the progression of atherosclerosis, especially when the levels of CT, LDL and TG are high and HDL is reduced31.

HBP is an independent risk factor for the occurrence of atherosclerotic vascular damage in lupus. Rahman et al. described an important association between hypertension, hypercholesterolemia and vascular events in SLE patients32. In the mentioned study, 50% of the patients presented alterations in BP. In a study by Telles et al., The most prevalent risk factor for CVD in lupus patients was hypertension, present in 48.8% of the individuals studied33.

CONCLUSION

In the present study it was possible to conclude that the individuals with the highest prevalence of MS were female adolescents, with ages ranging from 17 to 19 years old, attending high school, family income less than three minimum wages, obese, using antimalarial, sedentary and with disease time ranging from one to three years. As a limitation of the study, the absence of individual doses of corticosteroids used by adolescents during the research is exposed.

The metabolic syndrome is a serious public health disorder, and it is extremely important to monitor individuals at metabolic risk so that prevention and control measures can be established. Particularly, the young population with SLE may present along the therapeutic trajectory, metabolic dysfunctions with significant complications, and early monitoring to alleviate future intercurrences, especially the prevention of NCDs. In addition, healthy lifestyles, such as physical activity and balanced eating, are paramount for maintaining proper nutritional status. Therefore, this work alerts to the screening of MS in adolescents with SLE, so that more attention is paid to the early detection of metabolic abnormalities.

13. National High Blood Pressure Education Program Working Group on Hipertension Control in Children and Adolescents. The fourth report on the diagnosis, evaluation, and treatment of high blood pressure in children and adolescents. Pediatrics 2004;114:555-576.